Thread: 400 chev or 383?

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I'm at my wits end...I pulled my 400 chev out and brought it to the machine shop because the cam wouldn't come out. Got the cam out and installed new cam bearings. The machine shop asked how many miles were on this motor and I replied 200 miles. They said by the look of the cylinder walls it looks as though it had a ton of nitrous run through it. Which it hasn't. Supposedley the walls are scuffed pretty good and the engine will not last past 10,000 more miles. They said they could put it back together but wouldn't recommend it if I wanted it to last.
So here I am back at square one again. I'm thinking of maybe just getting a short block 383 or 400 and use my aluminum heads just to get back on the road again. I've contacted some engine companies to get a price on short blocks and heres what I cam up with.

Stock 355 chev 750.00 w/ 1 year warranty
stock 400 chev 875.00 w/ 1 year warranty
383 chev..........1700.00 w/ 1 year warranty

I think that price on the 383 is high. All i want is a strong small block that runs on pump gas and 425-450HP Is that to much to ask these days? I've had terrible luck. I'm probably in 4500.00 buck for the last 400 chev that is supposedley junk now. What would you guys do? This engine will go into my 79 10th anniversary trans am w/3.42 rear gears-th350 tranny-2300stall-1 5/8" headers-edelbrock 488/510 camshaft-2 1/2" exhaust. Anyone ever had this bad of luck? Any insight would be great....

I have a fresh 383 complete if interested.

I'm assuming your block if already at 0.030" over. Did you ask them about cutting/honing your block for 0.040" over pistons?

If I were going to buy a short block, I wouldn't pay a premium for a 383 over a 400 unit. That doesn't make any sense. They both have a 3.750" stroke for torque.

Who did the final assembly on your motor? If you, did you wash it to within an inch of its life and lube everything before you started bolting parts together?

The block was .40 over supposedley. Who knows with the shop that built and rebuilt it again. Can you hone a block that has a sleeve in it? My block has 1 sleeve in it because of a very small crack in the #3 cylinder wall.

How much for that 383?

I have $2500.00 in it . make an offer

"Can you hone a block that has a sleeve in it?"

Yes, but it sounds like that block is ready to be recycled. If you hone it to clean it up, you'll most likely have too much piston to wall clearance and it'll never be right. See if you can make a deal with pappy or opt for the 400 short block.

Pappy it sounds like you want more than I can spend right now...thanks anyway. I think I'll go the 400 route again even though I'm a bit leary. Hopefully I will be able to use some of my old parts. This hotrodding shit is getting expensive. My bad luck has got come to an end Soon I hope. Sometimes you feel like giving up. I'm pretty damn close

Denny, that would be a stock 400 I'm guessing it would have to be .30 over. How do you get over 400HP on that combo w/ a stock 400? I have aluminum heads w/2.02/1.60 valves and a holley 750cfm carb, edelbrock eps intake, and new 488.510 cam. Some insight on that issue would be great. I always thought that you need a real stout bottom end and fancy ass pistons and big bores to acheive that. Am I wrong? Can you get there w/ a stock motor and what I have for a top end? By the way the company is called gopher engine. And I have not found out about there warranty YET.

Horsepower and torque is in the heads first and foremost.
Crap heads with a $10,000 bottom end is a crap motor.

Anyone know of any proven 400plus HP buildups for a SBC 400. On Pump gas.

Scroll through these 100+ dyno-proven, pump gas builds. Look at the 383 results. You know that whatever hp and torque a 383 will produce, a 400 will also produce, only a little better. (same stroke)
http://www.ryanscarpage.50megs.com/combos1.html

With those heads the should be no problem going well beyond 400 hp on a 400sb assuming your cam isnt stock type lift. just buy a new block for $100 and spend what ever it cost at your shop to bore it and rebuild the 400. or as road agent said you could use a 350 block, but theres more to it than just clearancing the pan rails. You would need new pistons, have to mains turned down(costly) and might as well have it balanced while your at it.

Hi Onemangang. I will pass on advice my 86 year old dad that is still building racing engines for his grandson, gave me on my street rod engine. "There are more problems that you can have with the siamesed 400 block that you may not have with a 383. Build a 383 with a max .030 overbore and at least a 5.7" rod. Balance the rotating assembly, use a good rod, and don't run above 7000 rpm". If you intend to run this engine at a sustained high rpm, use a 4340 or better crank. As you can see, horsepower and reliability are expemsive. The 400 crank can be ground to fit the 350 block if you can find someone that is willing to do this. Hope this helps.

http://chevyhiperformance.com/techar.../148_0306_406/ This article shows how to do a 400 sleeper motor that roars for cheap. If the sleeve was done right they work good ( ran my bbc 8200 with one). Check piston to wall to see of a light hone may still keep you in specs, it may have been too tight to start with. 400 is a good engine if done right, double check everything.

Im no expert but before I did anything I would get that engine to another shop for a second opinion. If your not experienced enough to look at the cylinders wear and spec them yourself...then you definately need other opinions. Not to insult or put down your current builders but if you dont know them well ,how do you know they are not getting over on you for the business. Many times especially with regards to machine work and builders have I gotten 2 different opinions which made me research a whole lot more till I got a good census and prrof with my own eyes. JMO.